Metering pump



A, .c. WRIGHT METERING PUMP Jan. 13, 1970 2 Sheets-Sheet 1 Filed March 22, 1968 T R Q B E M Q \N o w T A [Q Q lmfIIIIiIFQ W m m mm NW1 N A [hllll l \m l m 5 Sq I IIITIII T E N S W Q Q H q I l II 1 1w H -H m 3 m I I I 1 1 1 I INI II W I I \R u r 1] I I! M g z [5, r I l 4 hm I ILJHIHFEKT 7 m mwn IL u M1 W Q fi i H H m A. C. WRIGHT METERING PUMP Jan. 13, 1970 2 SheetsSheet 2 Filed March 22, 1968 INVENTOR ALLE/V 6. WRIGHT H/S ATTORNEY United States Patent M 3,489,096 METERING PUMP Allen C. Wright, Moraga, Calif., assignor to Utility Products, Inc., a corporation of California Filed Mar. 22, 1968, Ser. No. 715,386 Int. Cl. F04b 43/08 U.s. c1. 103- 148 6 Claims ABSTRACT OF THE DISCLOSURE My invention relates to pumps and more particularly to metering pumps.

In known metering pumps, the pumping of abrasive or corrosive materials creates a serious problem due to the exposure of seals and packings to the material being pumped, leading to early failure of such seals and packings, with resulting shortened life of the pump.

Among the objects of my invention are r (1) To provide a novel and improved metering pump;

(2) To provide a novel and'improved metering pump in which there is an absence of exposed seals or packing;

(3) To provide a novel and improved metering pump capable of simultaneous pumping of two or more different liquids and in apredete'rmined'ratio; and A (4)'To provide a novel'and improved metering pump adaptable to a change of calibration.

Additional objects of my' invention will be brought out in the following description of a preferred form of the invention, taken iri'bofijunction 'with the accompanying drawings wherein, I

FIGURE 1 is'a view partly in' s'e'ction, of a metering pump 'embodying'the features'of the present invention; FIGURE-2 is a view of a system incorporating the pump of FIGURE 1;

' FIGURE 3 is a view in section, taken in the'plane 3-3 of FIGURE 1; and

' FIGURE 4 is a view insection, taken in the planes 4-4 of FIGURE 1.

Referring to the drawings for details of my invention in its preferred form, I provide one or more tubes 1 of flexible material, each tube being closed at one end by a valve controlled inlet coupling assembly 3, and at its other end by a valve controlled discharge coupling assembly 5. .Only one tube and its end assemblies have been illustrated in section, in that any other tubes involved in the pump, will be of similar construction, and a description of one will apply equally to the others.

The tube may be of any suitable flexible material, namely a material which is impervious to liquids and is capable of withstanding pulsations. Rubber or plastic are examples of such materials, with Teflon or other memory plastic being preferred where useable because of their heat shrinkable properties.

The intake coupling assembly provides for connecting the tube to a source 7 of liquid to be pumped. Such assembly includes a body component 9 having a flow passageway 11 therethrough, said body component includ ing a threaded neck section 12, connecting with an enlarged end or head 15, over which is stretched, an end of the tube, with the enclosing portion of the tube, if of Teflon or other heat shrinkable material, being heat shrunk into tighter fitting engagement therewith.

The enlarged end is preferably frusto conical in shape to receive a clamping collar 19 held in clamping engage- "ice inent against the enclosing portion of the tube by a lock nut 21 applied to the neck section of the body component.

The passageway through the body component is adapted to receive a ball check valve 25 adapted to seat against a seating ring 27 installed in the outer end of the passageway, and preferably formed of a material such as tung sten carbide, which is capable of minimizing wear due to flow of abrasive or corrosive materials in flow contact therewith.

Forward motion of the ball valve off its seat is limited by a restrictive ribbed insert 31 in the passageway.

A pipe fitting 33 threaded onto the outer exposed end of the neck section permits of a pipe connection to the source of supply 7 of liquid to be pumped.

At the discharge end of the tube, the coupling assembly 5 involves a somewhat similar body component 37, having a threaded neck section 39 and an enlarged head portion 41 of generally frusto conical shape, over which that end of the tube is stretched, with the enclosing portion of the tube, if of Teflon, being heat shrunk thereabout and the entire assembly then clamped to a mounting plate 45 by a lock nut 46 threaded onto the neck section of the body component.

This body component has a flow passageway 47 therethrough to receive a ball check valve 49 adapted to seat against a seating ring 51, preferably of tungsten carbide, recessed into the head end of the body component, against an O ring 53. Forward movement of the ball check valve off its valve seat, is limited by a ribbed insert 55 installed in the passageway.

A pipe fitting 57 mounted on the neck end of the body component, provides for a pipe connection 61 from the discharge end of the tube, and at the same time affords a stop for a valve spring 63 in the flow passageway and normally urging the ball check valve to its valve seat.

An 0 ring 65 installed in the pipe fitting, serves to seal the pipe fitting to the neck end of the body component, to inhibit leakage at this point. Rotatable movement of either body component in its installed position is inhibited by a radial pin 67 anchored in the body component and entering a groove provided in the proximate component such as the clamping collar 19 or the mounting plate 45.

The tube and its end couplings, as a unit assembly, is installed in a housing which defines a sealed chamber 71 about the tube, for holding a supply of pumping fluid 73 about the tube.

The housing is preferably cylindrical, including a cylinder 75 closed at one end by a wall, which may be the mounting plate 45, while at its other end, it is closed by a wall or plate 77 through which the intake coupling assembly 3 passes and to which it is bolted. For this purpose, the clamping collar 19 is provided with a flange 79 to receive mounting screws 81, an O ring 83 around the clamping collar and engaging the proximate edge of the opening in the end wall of the housing, serving to seal the chamber at this point.

Slideably entering the chamber through an end wall of the housing, and preferably that end wall formed by the mounting plate, is a displacement rod 87 reciprocally driven by any suitable motor 89, which in the present instance, is preferably an air motor. Such displacement rod, on its forward stroke into the housing, displaces a predetermined volume of liquid in the chamber, and inasmuch as the housing is sealed against escape of such liquid from the housing, the displaced liquid must seek other space and this can only be realized through compression of the tube, causing constriction thereof and to a degree necessary to provide such additional space.

As the displacement rod reverses its direction of movement, the reduction in pressure created thereby within the chamber causes the liquid in the chamber to immediately follow the displacement rod in response to the greater pressure existing within the tube, thus causing the tube to be restored to its original condition. Repeated reciprocation of the displacement rod will thus cause the tube to pulsate, and alternately take in a measured amount of liquid at one end, and then discharge an equivalent amount at the other end.

The amount of liquid taken in and then discharged during each reciprocation of the displacement rod, is a function of the diameter of the rod and its stroke, and thus such displacement may be altered by changing either or both.

Where a plurality of tubes are to be utilized, each will preferably be housed in its own housing, and be exposed to the reciprocation of its own associated displacement rod. In such case, a mounting plate, common to all of the housings may be utilized, and it will be so laid out that the displacement rod openings will be located around the center, whereby the displacement rods may be conveniently grouped for reciprocation by a common power unit, in which case the power unit will carry a bracket assembly 95 to which the various displacement rods may be bolted for simultaneous reciprocation.

The use of a multiple tube arrangement may be resorted to, to increase the capacity of the pump or to serve a very useful function in mixing two or more ingredients in predetermined ratio, necessary toward realizing a desired mixture. When employed in the latter sense, the discharge from each of the tubes will be directed to a mixer 97 in the proper ratios. Such ratios may be adjusted to satisfy conditions, by changing the relative diameters of the displacement rods.

To provide for this, guide sleeves 99 of like outside diameters but of different inside diameters are made available to slidably receive available rods of different diameters. Selected guide sleeves are removably installed, each in its own cylindrical housing 100, with the advancing end entering a recess in the mounting plate, concentric with the displacement rod opening, and carrying an O ring seal encircling the associated displacement rod.

The cylindrical housings are stabilized by welding them together and to the mounting plate 45, and are then capped to provide for mounting of the motor 89.

Suitably spaced bolt holes 101 in the mounting plate 45, permit of installation of the metering pump of the present invention.

The pump may be made double acting by arranging housings end to end and utilizing double ended displacement rods which can be reciprocated between end to end chambers to alternately displace liquid in such chambers.

From the foregoing description of my invention in its preferred form, it will be apparent that the same is subject to alteration and modification without departing from the underlying principles involved, and I accordingly do not desire to be limited in my protection to the specific details illustrated and described except as may be necessitated by the appended claims.

I claim:

1. In a metering pump of the type wherein a tube of flexible material is surrounded by liquid exposed to re- 4 ciprocal displacing means to pulsate said tube, means for flow connecting said tube of flexible material to a supply source of liquid to be metered, said means comprising a coupling assembly including a body component with a flow passageway therethrough and having an enlarged end inserted into said tube to be partially enclosed thereby, a check valve in said passageway, and means clamping the enclosed portion of said tube to the enlarged end of said body component.

2. A metering pump in accordance with claim 1, characterized by said tube being of heat shinkable material, with the enclosing portion of said tube heat shrunk into engagement with the enlarged end of said body component.

3. A metering pump in accordance with claim 2, characterized by a similar coupling means at the other end of said tube for flow connecting said tube to a discharge line.

4. A metering pump comprising a pair of tubes of flexible material, means for flow connecting each of said tubes of flexible material to a different supply of liquid, means for flow connecting both of said tubes to a common discharge line, a housing enclosing each of said tubes independently of the other and defining a sealed chamber about each of said tubes for holding a supply of pump fluid about each of said tubes, and means for cyclically and simultaneously displacing a fixed volume of said fluid in each of said chambers to cause simultaneous pulsations of said tubes of flexible material and effecting synchronous pumping of liquid from both of said supply sources in a fixed ratio in accordance with the ratio of fixed volume displacements in said chambers.

5. A metering pump is accordance with claim 4, characterized by said means for cyclically displacing a fixed volume of fluid in each chamber, including a displacement rod mounted for reciprocable movement in a wall of each of said chambers, means for reciprocating said rods in unison, and means for changing said ratio.

6. A metering pump in accordance with claim 5 characterized by said means for establishing a predetermined ratio of liquids pumped from said tubes, including a plurality of displacement rods of different diameters, and plurality of sleeves having different inside diameters corresponding to the diameters of said displacement rods, each of said sleeves being adapted to slidably receive its corresponding displacement rod, and all of said sleeves having like outside diameters.

References Cited UNITED STATES PATENTS 2,291,912 8/1942 Meyers 103148 2,735,642 2/1956 Norman a 103148 3,062,153 11/1962 Losey 103-148 3,148,624 9/1964 Baldwin 103-148 3,406,633 10/1968 Schomburg 103148 DONIYJEY J. STOCKING, Primary Examiner WILBUR I. GOODLIN, Assistant Examiner 

